The invention relates to a coupling part for a fluid coupling device, particularly a hose coupling, which has two coupling parts which can be brought into a coupling position by fitting into one another and which can be detached from one another by pulling apart.
Detachable fluid coupling devices of this type are e.g. known from quick coupling plug systems. In the case of the latter the substantially fluid-tight coupling position can be obtained by simply fitting into one another a coupling inner part and a coupling outer part. In quick couplings of this type, one of the coupling parts, generally the coupling outer part, has a switchable locking device, which is provided for locking the coupling parts in the coupling position in order to prevent an undesired pulling apart of the coupling parts. The locking device has at least one locking element mounted on a basic body of the coupling part and an actuating element cooperating therewith and which is frequently constructed as an actuating sleeve surrounding the basic body of the coupling part. As a result of a release movement of the actuating element directed in a release direction, the locking device can be shifted from a retaining position into a release position between a locking configuration and a release configuration. In the locking configuration the coupling parts fitted into one another in the coupling position are secured against extraction by the at least one locking element and can be drawn apart in the release configuration.
DE 17 75 302 discloses different embodiments of such fluid coupling devices, which are characterized by particularly easy operation. One embodiment operable with one hand has on the coupling outer part an actuating element in the form of a sleeve, which is axially displaceable relative to a basic body of the coupling part, in a holding position keeps the locking elements in the locking configuration and as a result of a longitudinal displacement of the coupling device releases the latter.
It has been found in practice that in this very advantageous embodiment as a result of its ease of operation, it can arise under unfavourable circumstances that the locking device is unintentionally shifted into its release configuration, e.g. by playing children or by a longitudinal movement of the hand of a user along a fluid line having the coupling. The unintentional fluid escape can in part have unpleasant consequences.
In another quick coupling type known from DE 34 90 017, a measure has already been proposed in order to make impossible or at least difficult such a chance or unintentional shifting of an actuating sleeve. For this purpose it is proposed to use a stop button carried by the actuating sleeve and movable in the direction of the longitudinal axis of the coupling and also away therefrom between a retaining position and a release position, whilst also having abutment means cooperating therewith in the retaining position thereof to prevent a movement of the actuating sleeve into the release position and after the disengagement of the abutment means the stop button can be moved into its release position. For unlocking the retaining position it is firstly necessary to depress the stop button and only then is it possible to displace the actuating sleeve. Although the resulting barrier for the actuating sleeve is effective, operation is cumbersome and the construction of the coupling device is made complicated as a result of the numerous cooperating parts.
The problem of the invention is to provide a simply constructed and easily operable coupling part of a fluid coupling device of the aforementioned type, where an unintentional disconnection of the coupling is reliably prevented.
This problem is solved by a coupling part having the features of claim 1 and a fluid coupling device having the features of claim 13. Advantageous further developments appear in the dependent claims. By reference the wording of all the claims is made into part of the content of the present description.
In such coupling parts the problem is solved in that the locking device can be blocked by moving the actuating element into a locking position and the actuating element is movable into a locking position blocking the release of the locking device. In particular, in the locking position the release movement of the actuating element is blocked. Due to the resulting, planned blockability of release of the coupling, for the disconnection of said coupling it is necessary to carry out a prior, deliberate moving back of the barrier, so that an unintentional disconnection can no longer occur. By a simple movement of the actuating element the barrier can be switched into the locking position and can be released again by a normally oppositely directed movement from the locking position. As a result of the invention the coupling part or actuating element, in addition to its known function, acquires a further functionality, without additional components-being needed for the provision of a barrier.
The locking position of the actuating element clearly differs from the retaining position. It is similar to the retaining position inasmuch as also in the locking position the locking elements are in a locking configuration preventing a disconnection of the coupling parts. However, unlike in the retaining position of the actuating element, for the release of the coupling no simple movement into the release position is possible and instead a more complex movement sequence is required, in which normally the actuating element must initially be moved back into the retaining position and then into the release position. It is improbable and excluded in practice that these two movements, which preferably are in opposite directions, are unintentionally performed or are initiated by chance due to external effects. Thus, fluid coupling devices equipped with the coupling parts according to the invention are particularly reliable in operation, without their handling being made significantly more complicated.
The invention can e.g. be implemented with quick couplings of the type disclosed by DE 34 90 017, in which the actuating member is actively brought into the release position for coupling in and must then be moved into its retaining position for locking the coupling parts. However, particular preference is given to embodiments in which the coupling parts can be brought into the coupling position without actuation and/or movement of the actuating element, because as a result the fitting together of the coupling parts can take place particularly rapidly and easily. Thus, the invention can be used with particular advantage in all quick coupling embodiments described in exemplified manner in DE 17 75 302, whose features are, by reference, made into part of the content of this description.
Therefore the situation can be such that the coupling part has a main or basic body, in which are provided several, e.g. three locking elements arranged around the circumference of the main body. The locking elements are preferably in the form of separate insert bodies, which are guided in axially fixed manner in openings of the main body and which in each case have cam sections provided for engaging on one another under the action of spring tension in an e.g. annular groove-like recess of the other coupling part, e.g. a hose nipple, for the purpose of locking together the coupling parts. On both axial faces the cam section appropriately has inclined surfaces in the manner of insertion bevels, so that inter alia the fitting together of the coupling parts without actuation or movement of the actuating element is aided. The actuating element is preferably an actuating sleeve which embraces the basic body at least in the vicinity of the locking elements and which has on its inside closing faces, which cooperate with the radial outsides or backs of the locking elements in such a way that in the retaining position of the sleeve the locking elements are radially supported to the outside and are so wedged between the inner part and the closing face that an outward movement is largely prevented, whereas in the sleeve release position an outward movement is possible permitting the pulling apart of the coupling parts. The switching between the retaining and release positions can take place by rotating the sleeve about its longitudinal axis or by axial sleeve displacement and in particular in the case of axial displaceability of the actuating sleeve between the retaining and release positions, a one-handed operation of the coupling is easily possible.
The preferably sleeve-like actuating element, although it can have a non-sleeve shape, is consequently preferably movably arranged with respect to the basic body of the coupling part, is preferably pretensioned in its retaining position and for releasing the coupling can be moved from the retaining position into the release position in a release direction, which is preferably the longitudinal direction of the coupling part or basic body. A particularly simple operation of the locking means is brought about in that the actuating element can be moved from the retaining position into the locking position by moving in a release direction at right angles and in particular perpendicular thereto. This locking direction is, in the case of a longitudinally displaceable actuating element, preferably the circumferential direction of the coupling, so that for locking the actuating element must be turned about the longitudinal axis of the coupling, starting from the retaining position. In the case of actuating elements, whose rotation brings about a coupling release, the setting of the locking position can take place correspondingly, e.g. by a longitudinal displacement of the actuating element.
In these preferred further developments the full functionality of the preferred coupling parts described e.g. in DE 17 75 302 are retained and a user can operate such couplings in the normal manner. According to preferred embodiments of the invention to said functionality with which the user is acquainted, is added a further functionality, namely the possibility of locking the coupling against unintentional disconnection as a result of a special movement of the actuating sleeve.
In preferred further developments this additional security function can be obtained without additional components on the coupling solely through appropriate modifications of the shape of existing components, more particularly as a result of the construction of the cooperating projections and recesses positive engagement elements are created which bring about the locking function. This is advantageously achieved in that the actuating element, preferably on its inside facing the basic body, has at least one stop running at right angles and in particular perpendicular to the release direction and which extends transversely to the release direction over a limited stop length and which cooperates with a counterstop of the basic body in such a way that the actuating element, starting from the retaining position and whilst bypassing the stop is movable in the release direction up to the release position and starting from the locking position by the stop striking against the counterstop in the release direction is blocked in such a way that a direct, linear movement into the release position is impossible. Thus, for release purposes, the counterelement must perform a detour round the stop, for which purpose the actuating element must be correspondingly moved, particularly rotated.
It is alternatively or additionally possible to provide at least one circumferentially bounded stop on the basic body and for a counterelement cooperating therewith to be located on the actuating element.
Particularly advantageous from the manufacturing standpoint are further developments in which the stop and/or counterstop are constructed in one piece with the component carrying the particular element, i.e. the actuating element or the basic body. Thus, inventively operating coupling parts can e.g. be inexpensively made from plastic, in that the moulds conventionally used for manufacture are slightly modified for shaping stops or counterstops.
To aid easy, faultless operation an indicating device can be provided, with the aid of which the blocked or unblocked state of the coupling can be rendered optically visible. For example, on the basic body and on the actuating element can be applied marks or signs, e.g. by imprints, whose relative position differs in the blocked and unblocked state.
Operational reliability and security can be increased in that latching means are provided for the latching securing of the actuating element in the retaining position and in the locking position and which are constructed in such a way that the actuating element can only be shifted between the retaining position and locking position by overcoming a latching resistance. Thus, both an undesired locking of the coupling and also an undesired unlocking are made more difficult and the actuating element remains in stable form in the given position.
These and further features can be gathered from the claims, description and drawings and, either singly or in the form of subcombinations, can be implemented in an embodiment of the invention and in other fields and can represent advantageous, independently protectable constructions.